Temperature and flow regulator



W. VINSON TEIPERATURE AND F'LCII REGULA TOR 5 Sheets-Sheet 1 Filed April 28. 1947 [/WENTQR v WALTER L. V/NSON BY H15 A rroRm-rs HA RR/S, Mac/4, FOSTER 4 HARRIS a #24252 Oct. 17, 1950 w. VINSON 2,526,099

' mum-rum: AND FLOW REGULATOR Filed April 28, 1947 5 Sheets-Sheet 2 375 I9 I99 me W8 i-m ll-u WALTER L. \//-5 0/v 8v HIS Ar'rvR eas HA ms, A4501, 1557-59 4 Ham/s Oct. 17, 1950 w, vmso 2,526,099

mPERA'ruRE AND FLOW REGULATOR Filed April '28, .1947 5 Sheets-Sheet 4 76 Saw/c5 LINE Ra Mun LINE // [NVENTQR WALTER L. V/NSON LINE Patented Oct. 17, 1950 I UNITED STATES PATENT OFFICE I mmmimefif'zlw naomnroa Walter L. vimon, Sherman oaks, c m. Application A ril as, 1941, Serial No. 144,395

My invention relates in general to fluid telliperature and flow regulating devices and, more particularly, to a device for mixing fluids of difierent temperatures and for delivering the resulting mixture at various selected rates and temperatures as desired by the operator of the device.

This application contains subject matter which is .disclosed and claimed in one or more of my copending applications entitled: Device for Regulating Fluid Temperatures, Serial No. 6'77,- 243, flied June 17, 1946; "Fluid Temperature Regulator, Serial No. 677,244, flied June 17, 1946, now abandoned; and "Flow Control Device, Serial No."l07,6'17, filed November 4, 1946, reference to which is hereby made. v

Since the fundamental principles of my invention were originally embodied in a device for delivering water to a shower head at selected rates and temperatures in accordance with the wishes of an individual desiring to take a shower, I prefer water, or other fluids of different tem eratures, from any suitable sources of supply in such proportions as to maintain the temperature of the resulting mixture substantially constant at a predetermined value regardless of normal temperature variations at the sources of supply, and which is adapted to deliver the mixture at a substantially constant rate regardless of normal pressure variations in the system. A related object is to provide a device of this nature which permits varying the mixture temperature and flow rate as required so that any desired temperature and flow rate within the capacities of the sources of supply may be selected.

It is a specific object of my invention to provide I a flow and temperature regulating device which,

when incorporated in a shower installation utilizing hot and cold water from conventional sources, is adapted to deliver water to the shower head at selected, substantially constant temperatures ranging from the temperature of the cold water 90laims. (01.236 42)- source to a maximum value, which may be the temperature of the hot water source, for example, regardless of normal temperature variations at the hot and cold water sources, and which is adapted to deliver water to the shower head at selected, substantially constant flow rates ranging from zero to a maximum rate corresponding to the pressures available at the sources or supply.

Anotherobject of my invention is to provide a regulating device which admits the fluids of different temperatures at relative rates such that the temperature of this mixture resulting from commingling of the fluids is maintained substantially constant at a predetermined, maximum value, an important object i'nthis connection being to providea device by means of which additional fluid of the lower temperature may be added to the mixture of maximum temperature manually, whereby the temperature or the flnal 20 mixture delivered by the device may be reduced to consider such an embodiment herein for conbelow the maximum temperature of the initial mixture in accordance with the wishes of any particular individual. A further object in this connection is to provide a device whereby the initial mixture and the colder fluid may be mixed in varying proportions so that the temperature of the fluid delivered by the device may be varied irom the temperature of the colder fluid to that of the initial mixture.

More speciflcally, it is an object of' the invention to provide a regulating device which includes inlet control means responsive to the temperature of the initial mixture of the fluids for regulating the relative rates of flow oi the fluids through inlet passages in the deviceso as to maintain the temperature of the initial mixture substantially constant at a predetermined maximum value, and which includes manually operable means associated with an outlet passage in the device for introducing into the outlet passage an additional quantity oi. the fluid or lower temperature so as to reduce the temperature of the initial mixture produced by the inlet control means from the maximum value, thereby producing a flnal mixture of the desired temperature.

Since the flnal mixture is controlled manually by reducing the constant, maximum temperature of the initial mixture through the addition or fluid or the lower temperature, the only function of the inlet control means is to compensate for any variations in the temperatures of the fluids entering the device, whereby it maintains the temperature of the initial mixture more nearly constant at the maximum value. Thus, the operat onot the inlet control means is not ina 3 fiuenced by changes in the final mixture temperature since such changes may be made manually without changing the maximum temperature at which the initial mixture is maintained. As a result, the temperature of the magor portion of the mass of the structure of the device is maintained substantially constant regardless of stant at a predetermined value. A related object is to provide a device wherein the flow control means is adjustable to change the rate of flow of the final mixture in accordance with the wishes of the particular individual using the device.

A further object of the invention is to provide a regulatin device which includes means for equalizing the pressures of the fluids entering the device so that the inlet control means regulating the relative rates of flow through the inlet passages may operate on fluids of equal pressures. This construction avoids requiring the inlet control means'to compensate for pressure fluctuations at the sources of supply so that it will maintain the initial mixture temperature more nearly constant at the desired maximum value, which is an important feature of the invention. Another object in this connection is to provide a pressure equalizing device which is hydraulically balanced in all directions for more sensitive operation.

"Still another obiect is to provide a device of the foregoing general character which includes outlet control means responsive to the temperature of the initial mixture for delivering the final mixture to a by-pass outlet until the initial mixture is at a temperature differin from the maximum value by a predetermined, small amount, and for subsequently delivering the final mixture to a service outlet, whereby the final mixture is not delivered to the service outlet untl it approaches the temperature selected by the operator. In a shower installation incorporating my regulating device, the by-pass outlet may lead to a suitable drain, and the service outlet leads to the shower head.

A further object in connection with the foregoing is to provide means for automatically draining the service outlet when the device be-v gins to 0001 after we so that the operating cycle of the outlet control means is repeated during subsequent use.

An additional object of my invention is to provide the regulating device with manually operable means for causing the outlet control means to close the by-pass outlet and open the service outlet independently of the temper ture the initial mixture so that the final mixture delivered to the service outlet may be at the temperature of the colder fluid enterin the device, if desired. Thus, when my regulat ng device is incorporated in a shower in tallation, if a cold shower is desired, the outlet control m ans may be actuated manually to deliver cold water to the shower head through the service outlet regardless of whether the initial mixture temperature is up to the predetermined maximum value. Consequently, the regulating device may be used for supplying cold water in a shower installation without any necessity'for having any hot water enter the device, which is another important feature of the invention.

Another object in connection with the foregoing is to provide a regulator having a single knob or other control member for governing the temperature of the final mixture, and for causing the outlet control means to open the service outlet and close the by-pass outlet independently of the initial mixture temperature when the temperature of the final mixture is set for a value close to that of the colder fluid. Preferably, by nsoving the temperature control knob throughout its range of travel, the temperature of the flnal mixture delivered to the service outlet is varied between the temperature of the colder fluid entering the device and the predetermined, maximum temperature of the initial mixture, and by moving the temperature control knob to a position at one end of its range of travel wherein the temperature of the flnal mixture delivered to the service outlet is equal to, or substantially equal to that of the colder fluid, the outlet control means is actuated to open the service outlet and close the by-pass outlet independently of the temperature of the initial mixture so that the colder fluid only may be delivered to the service outlet, if desired.

An important object of my invention is to provide a regulating device of. the character described which includes means responsive to temperature for interrupting flow through the device in the event that the temperature of the final mixture flowing through the outlet passage exceeds a specified value, this value preferably being a few degrees higher than the specified maximum temperature of the initial mixture. A related object is to provide flow interrupting means which responds to excessive fluid temperatures substantially instantaneously to interrupt flow through the device, the flow preferably being interrupted before any of the fluid at an excessively high temperature reaches the end of a service line connected to the service outlet of the .device. Thus, in the event of any failure or malfunctioning of any component of my regulating device which would result in delivery to the service outlet of fluid at an excessively high temperature, the flow interrupting means terminates all flow through the device, which is an important feature of my invention particularly when incorporated in a shower installation.

I contemplate a temperature and flow regulating device wherein the inlet control means includes thermostatically operated valve means for mixing the fluids of different temperatures, an important object in this connection being to provide a mixing valve means which is adapted to produce relatively thin, annular streams-of the fluids which intersect in such a manner as to insure thorough mixing. Another object in this connection is to provide a regu'ating device wherein the annular streams produced by the mixing valve means are of a generally conical shape and are symmetrical about a common axis, one of these streams being convergent and the other divergent to insure thorough mixing of the fluids.

The mixing valve means is preferably operated y t e ostatic means which is exposed to the means is disposed.

terconnected reservoirs fllled with an operating fluid which is adapted to expand-and contract in response to temperature ,variations, one of the reservoirs being rigid and the other being. expansible and contractible. This construction permits the use of a larger body of operating fluid than would otherwise be possible so that the volume changes of the operating fluid for given temperature changes are increased, thus increasing or amplifying the amount of expansion or contraction of the expansible reservoir for a given temperature change, which is an important feature of the invention.

One of the objects of my invention in connection with the thermostatic means is to provide a construction wherein the rigid reservoir is of tubular form' and surrounds the expansible and contractible reservoir so that the initial mixture to which the thermostatic means is exposed may flow in an annular passage between the two reservoirs, or may flow in another annular passage between the rigid reservoir and the wall of a mixing chamber in which the thermostatic Another and important object in this connection is to distributethe flow through these annular passages in such a manner as to obtain substantially uniform heat exchange between the initial mixture and all portions of the temperature sensitive operating fluid in the reservoirs.

Still another object in connection with the thermostatic means is to provide a construction wherein the reservoirs are initially filled with operating fluid while the fluid is at a temperature slightly less than the desired maximum temperature of the initial mixture and while the expansible and contractible reservoir is compressed to substantially its minimum length. By filling the reservoirs under such conditions, the

expansible reservoir will remain contracted to its minimum length as long as the temperature of the operating fluid is at or below the temperature provided during the initial filling operation, and will not begin to expand until the initial mixture temperature exceeds the temperature at which the reservoirs were filled. The foregoing provides for maximum flow of the hotter fluid until the initial mixture temperature approaches its predetermined maximum value so maximum temperature of the initial mixture is more rapidly attained, which is an important fea-' ture of the invention.

Another object is to provide means for adjusting the thermostatic means so as to vary the maximum temperature at which the initial mixture is maintained, such adjusting means preferably being set semi-permanently when the regulating device is manufactured or installed to prevent tampering with the setting by unauthorized persons. 1

Other objects of my invention include the provision of a temperature vice which is compact, which may be formed of parts that are simple to manufacture and assemble, and which may be manufacturedto sell at a relatively low price. i

The foregoing objects and advantages of my invention, together with various other objects and advantages which will be evident herein after, may be realized by means of the exemplary embodiment which is illustrated in the accompanying drawings and which is described in detail hereinafter. Referring to the drawings:

Fig. 1 is a fragmentary, front elevational view that the and flow regulating decold water, respectively,

wall i1 and are connected to the regulator I in a suitable disposal point such on a reduced scale of a shower installation incorporating a fluid temperature and flow regulator which embodies the fundamental principles of my invention;

Fig. 2 is a side eievational lator on a reduced scale;

Figs. 3 and 4am sectional views which are taken along the broken lines 3-3 and 4-4, respectively, of Fig. l;

Figs. 5 and 6 are sectional views which are 8I, re-

view of the re utaken along the broken lines 5-5 and spectively, of Fig. 3;

Fig. '7 is a fragmentary sectional view which is taken along the broken line 1-1 of Fig. 4;

' Fig. 8 is a diagrammatic view showing the flow through the regulating device;

Fig. 9 is a fragmentary sectional view duplicating the right one-half of Fig. 4 on an enlarged seal and Fig. 10 is a fragmentary sectional view duplicating a portion of Fig. 3 on an enlarged scale.

, For convenience in disclosing the invention, I prefer to consider a specific embodiment thereof in connection with a shower installation with the knowledge that my disclosure will enable those skilled in the art to employ the specific embodiment disclosed herein for other purposes and to devise other embodiments. Consequently, it will be understood that I do not intend to be limited to the specific embodiment and application of my invention which are disclosed herein for purposes of illustration.

Referring particularly to Figs. 1 and 2 of the drawings, my temperature and flow regulator is indicated generally by the numeral l5 and is shown mounted in an opening 16 in a wall II which, for example, may be awall of a stall shower (not shown). Inlet lines l8 and I! for hot and are located behind the a manner to be described in detail hereinafter,

' the inlet lines being connected to suitable sources of supply (not shown). A by-pass or waste line 20 is connected to the regulator l5 and leads to as a sewer line (not shown), for example, the regulator being adapted to discharge the water delivered thereto through the inlet lines l8 and I9 into the waste line 20 under certain operating conditions which will be described hereinafter. A service line 2| is connected to the regulator 15 and leads to a shower head 22, the shower head being mounted on the wall I! in the conventional manner.

The regulator i5 is provided with control elements and 26 for selecting the rate of flow of water to the shower head 22 and for selecting the temperature of the water to be delivered to the shower head, respectively, the control elements preferably being ribbed knobs, as shown in the drawings, for convenient manipulation by the operator. The control knobs 25 and 26 are rotatable relative to the body of the regulator l5 and are preferably provided with flanges 21 and 28, respectively, having lines or other indicia thereon which may be used in connection with pointers 29 and 30 'to obtain various flow rates and temperature settings, respectively, as will be described in more detail hereinafter. Thepointers are preferably carried by a panel 3| which covers the opening IS in the wall H to conceal the body ofthe regulator 15, thereby providing a shower installation having an attractive appearance.

-upon rotation of the flow control knob trol knob 26 to indicate the required to increase or decrease the rate at which water is delivered by the regulator II. As will be discussed hereinafter, rotation of the flow control knob 26 inthe direction of the arrows 23 and 34 respectively increases and decreases the flow rate, flow through the regulator I! being terminated to the end of its travel in the direction of the arrow 34. If desired, the words "on and of! may be placed on the panel 3| adjacent the arrows 23 and 34, respectively, as shown in Fig. 1 of the drawings, for convenience in varying the flow rate.

Similarly, the panel Si is provided with arrows 36 and 86 thereon adjacent the temperature control knob 26 which respectively indicate the directions of rotation required to increase and decrease the temperature of the water delivered by the regulator II. If desired, the words hot and "cold may be placed on the panel 3! adjacent the arrows 35 and 36, respectively, so that the operator may readily ascertain the direction of rotation of the temperature control knob 26 which is required to increase or decrease the temperature of the water delivered by the regulator.

It will be apparent from the preceding discussion that the operator of my temperature and flow regulatingdevice may select temperatures and flow rates through the manipulation of only two control elements, rotation of the control knob 25 serving to vary the flow rate, and rotation of the knob 26 serving to vary the temperature. The manner in which rotation of the control knobs 25 and 26 produces such flow rate and temperature variations will be explained in detail hereinafter.

The general construction and operation of the temperature and flow regulator i 5 will now be considered with particular reference to Fig. 8, wherein the regulator is shown semi-diagrammatically. The inlet lines l8 and i9 communicate with inlet passages 4i and 42, respectively, which lead to means 43 for equalizing the pressure of the hot and cold water entering the regulator I5. From the pressure equalizing means 43, the hot water and cold water flow through inlet passages 44 and 46, respectively, into a primary mixing chamber or zone which is indicated generally by the numeral 46. The regulator i5 includes temperature responsive inlet control means 48 for regulating the relative rates of'fiow of the hot water and the cold water through the inlet passages 44 and 45 in such a manner as to produce in the primary mixing chamber 46 an initial or primary mixture of a substantially constant, maximum temperature. The inlet control means 48 includes primary mixing valve means 49 for governing the relative rates of flow of the hot and cold water into the primary mixing chamber 46, and includes thermostatic means 50 exposed to the initial mixture in the primary mixing chamber for controlling the operation of the primary mixing valve means in such a manner as to maintain the temperature of the initial mixture substantially constant at the predetermined maximum value. The inlet control means 48 also includes means SI for adjusting the thermostatic means 50 so as to permit varying the predetermined or maximum temperature at which the initial mixture is maintained, the adjusting means 5i preferably being accessible only to service personnel so that persons normally operating the regulator l5 cannot change thesetting of the thermostatic means. As will be discussed in more detail hereinafter, when the regulator i5 is indirection of rotation temperature the primary-mixing chamber 46 and which leads to a secondary mixing chamber 0! zone 66, the latter being connected to the inlet passage 46 for cold water by an auxiliary inlet passage 56. Thus, the initial or primary mixture at the maximum temperature may flow into the secondary mixing chamber 56 through the intermediate passage 54, and cold water may flow through the auxiliary inlet passage 66 into the secondary mixing chamber, the relative rates of flow of the initial mixture and of cold water into the secondary mixing chamber being controlled by manually operable, secondary mixing valve means 61. As will be discussed in more detail hereinafter, the secondary mixing valve means 51 is actuated by the temperature control knob 28 so that the person taking a shower may introduce sufllcient cold water into the initial mixture to produce a secondary, or final mixture of a temperature less than the maximum value as desired.

In order to eliminate any possibility of scalding the person taking a shower in'the event of mal-functioning or failure of the thermostatic means 50, or any other component of the regulator IS, the regulator is preferably provided with means 60 responsive to the temperature of the final mixture for interrupting all flow through the regulator. The flow interrupting means 60, which is preferably located in an outlet passage 6i leading from the secondary mixing chamber 55, is preferably responsive to a final mixture of, for example, 2 F. above the predetermined or maximum temperature of the initial mixture. Thus, if the thermostatic means 50 is set for a temperature of F., for examp16, as the highest temperature which the average person can withstand reasonably comfortably. the flow interrupting means 60 is preferably responsive to a temperature of 117 F., for example. However, any desired temperature settings for the thermostatic means 50 and the flow interrupting means 60 may be employed and it will be understood that I do not intend to be limited to the specific values mentioned. I

The outlet passage 6| in the regulator i5 leads to manually adjustable flow control means 62 for maintaining the rate of flow of the final mixture substantially constant at a predetermined value, the flow control means 62 being responsive to pressure variations in the final mixture as will be discussed in more detail hereinafter. The flow control means 62 is actuable by the flow control knob 25 so that the person taking a shower may select any desired flow rate merely by rotating the knob 25, whereupon the flow control means maintains the selected flow rate substantially constant by responding to pressure variations.

The regulatm-"IS is provided with an outlet passage 63 which is a continuation of the outlet passage. 6| and which leads from the flow control means 62 to branching by-pass and service outlets 64 and 65, respectively, the waste line 20 being connected to the by-pass outlet 64 and the service line 2! leading to the shower head 22 by-pass outlet 64 as would normally be the case.-

S 3 being connected to the service outlet 65. The regulator I5 includes outlet control means 68 associated with the by-passand service outlets 64 and 65 for delivering the final mixture to .the by-pass outlet until the initial mixture reaches, or substantially reabhes, the maximum value-and for subsequently delivering the final mixture to the service outlet. The outlet control means 68 includes hydraulically operable outlet valve means 69 for diverting the final mixture either into the by-pass outlet 64, or the service outlet 65, and includes control valve, means or pilot valvemeans 10 for delivering operating fluid, preferably water in the particular construction illustrated, to the hydraulically operable outlet valve means; Aswillbe discussed in more detail hereinafter, the pilot valve means '10 is actuable to deliver operating fluid to the outlet waive; 1

means 69 by the thermostatic means 50 when i the temperature of the initial mixture reaches, or

substantially reaches, the predetermined or maximum value. However, the pilot valve means I0 may be actuated by other thermostatic means if desired.

It will be noted that since the pilot valve means 10 is actuable by the thermostatic means 50 in the particular construction illustrated, the final mixture will not be delivered to the service butlet 65 unless the temperature of the initial mixture in the primary mixing chamber 46 is sufficiently high to actuate the pilot valve means. Consequently, if the regulator I5 is to be used to deliver cold water only to the service outlet 65 for a. person desiring a. cold shower, it'is necessary, under the condition, that the outlet control means 68 be .tctuable to deliver the cold water to the service outlet independently of the temperature of the initial mixture. Accordingly, I

vprovide mean 'II foractuating'the. outlet valve means 69 independently of the pilot valve fmeans 10 so that operating fluid will be deliveredtofthe outlet valve means 69 even if the temperature of the initial mixture in the primary mixing chamber 46 is not equal to or substantially equal to the maximum value. The actuating means II is preferably operatively associated with the secondary mixing valve means 51 and, aswill be dis-, cussed in more detail hereinafter, is preferably adapted to by-pass the pilot valve means 10 when the temperature control knob 26 has been rotated to the end of its travel in the direction of the arrow 36 (see Fig. 1). When the temperature control knob 26 is in this position, the secondary mixing valve means 51 is preferably in a. position such thatit prevents, or substantially prevents flow of the initial mixture into the secondary mixing chamber 55 while, permitting cold water from the auxiliary inlet passage 56 to flow thereinto. Thus, when the temperature control knob 26 is rotated to the end of its travel in the direction of the arrow 36, the secondary mixing valve means 5'! permits cold water only to enter the outlet passage 6| and, at the same time, the actuating means II by-passes the pilot valve means I0 to deliver operating fluid to the hydraulically operable outlet valve means 69, whereupon the outlet valve means delivers the cold' water to the service outlet 65, and thence to the shower head 22, instead of delivering it to the With the foregoing general discussion of the construction and operation of the regulating de-' vice I5 inmind, the various components of the devicewillnow be considered in more detail. As best shown in Figs. 1 and 5, the inlet lines I8 and 7 The body or the regulator I5 tapered annular V I9 for the hot and cold water are threadedly coii nected to special elbows 15 and I6, respectively, the elbow 15 being provided with intersecting passages TI and 18 therein and theelbow 16 being provided with similar passages 19 and 80.;-

provided with seats 83 and 84 for complemen'tarily tapered annular surfaces 85 arid 86 oil the elbows I5 and 16, respectively, the elbows being secured-to the bodyof the regulator b? a bolt 81' which retains'the taperedsurfaces 85 and 86 on the respective elbows in fluid-tight engage ment with the annular seats 83 arid 84 in th body or the regulator. It will be noted that the bolt 81 extends through openings 88 and 89 inthe elbows 15 and 16, respectively, and through an opening 90 in the body of the regulator I5, the opening 88 being sealed by an annular washer 9| preferably'formed of soft metal, which is compressed between the elbow' I5 and a nut 92 threaded on the end of the bolt 81, and the opening 89 being sealed by a similar washer 93 which is compressed between the elbow I6 and the head 94 of the bolt. The bolt 81 is sealed with respect to the opening 90 in the body of the regulator I5 by an annular sealing element 95, preferably formed of rubber or a similar material, which encircles the bolt and which is secured with respect to the body of the regulator by an annular rib 96 encircling the opening 90 and extending into a complementary groove 91 in the sealing element;

As best shown in Fig. 5 of the drawings, the passage I8 in the elbow I5 registers with a bore |0I which communicates with the inlet passage 4| leading to the pressure equalizing means 43. Similarly,- the passage 80 in the elbow 16 registers with a bore I02 which communicates with the inlet passage 42 leading to the pressure equalizing means. It will be noted that the sealing element 95 which was described in the preceding paragraph separates the inlet passages 4| .and 42.

'43, the latter being disposed in a bore I03 which extends through the'body of the regulator I5, as best shown in Fig. 6, and which intersects the inlet passages 4|, 42, 44 and 45. The inlet passages 4| and 42 for the hot and cold water are. separated by a wall I04 through which the bore I03 extends/to provide a cylindrical seat I05 for a. piston-like valve element I06 which forms part of thepressure equalizing means 43 as will be discussedin more detailhereinafter. The inlet passages 4| and 44 for the hot water are separated by a wall I09 through which the bore I03 extends to provide a cylindrical seat ||0 for a piston-like valve element III which also forms part of the pressure equalizing means. Similarly, the bore I03 extends through a wall 2 separating the inlet passages 42 and 45 for the cold water to provide a cylindrical seat I I3 for a' piston-like valve element H4. The ends of'the bore I03 are sealed by heads H1 and H8 which are so positioned with respect tothe valve ele-- ments III and H4, respectively, as to'provide a ment I I land the head I I1, and to provide fluid-tight seal between the heads and the body 01 the regulator is provided by sealing rings I23" .may be formed separately if desired. the valve elements I06, III and H4 move in unisonin the bore I03 to equalize the pressures of the hot and the cold water as will be discussed in more detail in the next paragraph. The valve element III is provided with a spiral groove I28 therein which leads from the inlet passage 44 for the hot water to the space II9 between the valve element III and the head II1. Similarly, the valve element H4 is provided with a spiral groove I30 therein which provides fluid communication between the inlet passage 45 for the cold water and the space I20 between the valve element H4 and the head H8. The use of the spiral grooves I29 and I30 providing fluid communication between the inletpassages 44 and 45 and the spaces H9 and I20,,';1'7espectively, insures that the valve elements III and II4 will be substantially balanced hydraulically insofar as pressure forces transversely of the bore I03 are concerned so that there is substantially no tendency for the valve elements to bind in the bore.

It will readily be apparent that since the spiral groove I29 connects the inlet passage 44 to the space II9, the pressure of the hot water in the inlet passage 44 is communicated to the outer end of the valve element I I l. Similarly, the pressure of the cold water in the inlet passage 45 is communicated to the outer end of the valveelement II4. Consequently, if the pressures of the hot water and the cold water diifer, the pressure equalizing means 43 will be unbalanced and will move in the bore I03 in the direction of the net pressure force. Thus, if the pressure of the cold water exceeds that of the hot water, for example, the pressure equalizing means 43'will tend to move toward the left, as viewed in Fig. 6, whereby the valve element III moves away from its seat I III to decrease the resistance to flow of the hot water from the inlet passage H to the inlet passage and, at the same time, the valve element II4 moves toward its seat II3 to increase the resistance to flow of the cold water from the inlet passage 42 to the inlet passage 45. Such movement of the pressure equalizing means 43 toward the left, as viewed in Fig. 6, continues until the resistances .to flow of the hot water and. cold water have been decreased and increased, respectively, to such extents that the pressures of the hot and cold water in the respective inlet passages 44 and 45 are substantially equal. Thus, the pressure equalizing means 43 continuously hunts a position such that the pressures of the hot water and the cold water in the inlet passages 44 and 45 leading to the inletcontrol means 48 are always substantially equalized. Moreover, if the flow of cold water in the inlet passage 42 a should be interrupted for, any reason, the pressure of the hot water would displace the pressure equalizing means 43 to the right, as viewed in Fig. 6, a suflieient distance to seat the valve element III so as to shut off the flow of hot water also. Thus, the pressure equalizing means 43 eliminates any possibility of scalding the person taking a shower. in the event of failure of the cold water supply, which is an important feature of the invention. It will be apparent that the pressure equalizing means will also operate to terminate 12 now of cold water in the event of any interruii tion in the flow of hot water in a similar manner. As previously discussed, the inlet passages 44 and 45 convey the hot water and the cold water,

' respectively, from the pressure equalizing means 43 to the primary mixing chamber 46, the inlet control means 48 being adapted to regulate the relative rates of flow of the hot and cold water into the primary mixing chamber in such a manner as to produce an initial or primary mixture of a substantially constant, maximum temperature. As best shown in Fig. 3, the primary mixing valve means 49, which forms part of the inlet control means 48, includes a mixing valve I which is slidable in a bore I35 in an insert member I31, the insert member being disposed in one end of the primary mixing chamber 46 and being seated against a shoulder I38 formed therein. The insert member I31 is retained in the primary mixing chamber 46*by a snap ring I39 which is disposed in an annular groove in the body of the regulator I5, a fluid-tight seal be tween the insert member and the body of the regulator being provided by an annular sealing element I which is disposed in a complementary groove in the insert member.

As best shown in Fig. 3, the insert member I31 is provided with annular inlet passagesI44 and I45 therein which encircle the mixing valve I35 and which are separated from each other by a partition or wall I46. The inlet passage I44 in the insert member I31 communicateswith the inlet passage 44 for hot water in the body of the regulator I5, and the inlet passage I45 in the insert member communicates with the inlet passage 45 for cold water.

The mixing valve I35 includes a generally cupshaped element I41 which includes a base wall I 48 having a tubular stem I49 extending therefrom, the cup-shaped element being provided with a tapered edge or rim I50 which is adapted to seat against the base wall I5I of the bore I36 in the insert member I31 to prevent the flow of cold water from the annular inlet passage I45 into the interior of the mixing valve. The base 'wall I48 of the cup-shaped element I41 is provided with a plurality of openings I 52 therethrough to permit the flow of cold water entering the interior of the mixing valve I35 into the upper portion thereof, as viewed in Fig. 3.

The mixing valve I35 also includes an annular collar I56 which is seated in a complementary recess in the cup-shaped element I41, the annular collar being soldered or otherwise secured to the cup-shaped element of the mixing valve. The annular collar I56 is provided with a tapered edge or rim I 58 which is adapted to enter the mouth I60 of the bore I36 in the insert member I31 to prevent the flow of hot water from the annular inlet passage I44 into the upper portion of the primary mixing chamber 46, as viewed in Fig. 3, the mouth I60 having a tapered, annular entering surface I59. It will be noted that when the tapered rim I58 of the collar I56 is spaced from the tapered annular surface I59, the hot water flowing from the annular inlet passage I44 into the primary mixing chamber 46 will be discharged into the primary mixing chamber in the form of a relatively thin, convergent annular stream of generally conical shape, this stream being symmetrical about the axis AA of the primary mixing chamber. The cold water flowing into the primary mixing chamber 4'5 from the interior of the mixing valve 45 is deflected by a generally conical flange IN on the stem I 49 of 13 the cup-shaped element I41 to produce a generallyeonical, annular stream which is similar to the stream of hot water discharged into the primary mixing. chamber except that it is divergent insteadof convergent. Thus, the streams of hot and cold water discharged into the primary mixing chamber 46 intersect to insure thorough and almost instantaneous mixing, the angle of intersection of the two annularstream's preferably being of the approximate order of'magnitude of 96 as illustrated in Fig. 3 of the drawings.

It will thus be' apparent that the primary mixing valve means 48 controls the relative rates of flow, of the hot and cold water into the primary mixing chamber 46 and mixes thehot and .cold water thoroughly to produce-the pro-- viously discussed initial or primary mixture. As will be discussed in detail in the following para graphs the thermostatic means 56 is exposed to this initial mixture and varies the position of the mixing valve I35 in its bore I36 in such a manner as to maintain the temperature of the initial mixture substantially constant at the specified maximum value.

As best shown in Fig. 3, the thermostatic means i 56 includes an expansible and contractible primary reservoir I65, which is preferably in the form of a bellows, and includes a rigid, secondary reservoir I66 of generally tubular form which encircles the bellows-and is spaced therefrom, the secondary reservoir also being spaced from the peripheral wall of the primary mixing chamber 46. As will be discussed in more detail hereinafter, the initial mixture may flow upwardly, as

' viewed in Fig. 3, between the bellows I65 and the 'for a rod I14 which forms part of the thermostat adjusting means 5|, the adjusting rod being threaded in a bore I15 in the insert member I31. The adjusting rod I14 may be locked in any desired position by means of a nut I16 which is threaded thereon and which seats against the exterior face of the insert member I31. Leakage between the adjusting rod I14 and the insert member is prevented by a sealing ring I11 which is disposed in an annular recess in the insert member.

The secondary reservoir I66 is preferably .formed of two concentric tubes I8I and I82 which are preferably formed of copper orother material having a high co-efllcient of heat conductivity. The inner tube I8I is provided with an inwardly rolled end I83 which is soldered or otherwise secured to an annular flange I64 on the head member I68, and is provided with an inwardly rolled end I65 which is secured to the tubular stem I48 of the mixing valve I35. Similarly, the outer tube I82 is provided with inwardly rolled ends I81 and I88 which are suitably secured to the inner tube IN to provide the secondary reservoir I66. Fluid communication between the bellows I65 and secondary reservoir I66 is provided bypassages I68 and I86 in the head member I68 and by a tube I8I, this tube communicating .wltlitbe secondary reservoirand with the bore 14 1 I86, and. the bore I88 communicating with the bellows.- p v It will be noted that the mixing valve I38, the 'secon ary reservoir I66 and the head member I66 are a v rigidly connected and are movable in unison axially of the primary mixing chamber 46, the bore I36 in the insert'member I31 serving as a guide. The head member I68 is provided with a cylindrical projection I8 5 which is slidable in a bore I86 in the body of the regulator I5 to provide an additional guide'for such axial movement of the mixing valve .I35, the secondary reservoir I66 and the head member I68. As will be discussed in more detail hereinafter, the projection I85 is also adapted to actuate the pilot valve means 16, leakage past this projection being prevented by a sealing ring I81 which is disposed in an annular groove I88. It will be noted that the mixing valve I35 is normally urged downwardly, as viewed in Fig. 3, bya spring I88 which tends to prevent the flow of cold water from the annular inlet passage I45 into the interior of the mixing valve by seating the tapered rim I56 of the mixing valve against the wall I5I of the insert member I31,- the spring being disposed between the flange I64 on the head member I68 secondary reservoir is provided with a plurality of openings 262 therein, as best shown in Figs. 3

and 6. Similarly, the inwardly rolled end I63 of the tube I8I is provided with a plurality of openings '203 therein, as shown in Figs. 3 and 4.

As will be discussed in more detail hereinafter;.

the bellows I65 and the reservoir I66 are filled with an operating fluid which is adapted to expand andcontract in response to increases. and decreases, respectively, in the temperature of the initial mixture in the primary mixing chamber 46. Since the exterior surface area of the reservoir I66 is larger than the interior surface area of the inner tube I8I, and since the wall of the primary mixing chamber is also a, heat exchanging surface, the dimensions of the openings-202 and 283 which permit the initial mixture to'flow between the bellows and thereservoir are preferably such that only a relatively small portion of the initial mixture may flow through the space between the bellows and the secondary reservoir, whereby the major portion of the initial mixture flows through the space between the secondary reservoir and the peripheral wall of the primary mixing chamber 46. The distribution of the flow of the initial mixture past the bellows I65 and the secondary reservoir is preferably such that the relative rates of flow through the space between the bellows and the secondary reservoir I66 and through the space between the secondary reservoir and the peripheral wall of the primary mixing chamber 46 are approximately propor-. tional to the relative surface areas of the bellows plus the area of the inside of the tube I8I and the exterior of the tube I82 plus the area of the wallof the primary mixing chamber 46 so as to produce a more uniform heat exchange between the initialmixture and the operating fluid. Inother words, such a flow distribution causes the temperature of the operating fluid to change at suband the end wall of the primary mixing chamber stantially the same rate at all points in the bellows I65 and the secondary reservoir I66 in the event of a temperature change in the initial mixture to provide a more uniform response, which is an important feature of the invention.

Before discussing the remainder of the structure of the regulating device I in detail, the operation of the thermostatic means 50 will now be considered for convenience. As previously discussed, the spring I99 tends to seat the tapered rim I50 of the mixing valve I35 so as to prevent flow of cold water into the primary mixing chamber 46 from the annular inlet passage I45. At the same time, the spacing between the rim I58 of the mixing valve and the annular surface I59 encircling the mouth I60 of the bore I36 is a maximum so that hot water from the annular inlet passage I44 may flow into the primary mixing chamber 46 at a maximum rate. The mixing valve I35 remains in this position until the temperature of the operating fluid in the bellows I65 and the secondary reservoir I66 has been elevated sufliciently by the hot water entering the primary mixing chamber 46 to begin expanding the bellows. If the regulator I5 has not been in use for some time, the water in the inlet line I8 leading to the source of hot water supply may have cooled off so that expansion of the bellows I 65 will not begin until such cooled water has all been displaced by hot water from the source of supply.

After the temperatureof the water entering the primary mixing chamber 46 has increased .sufliciently to expand the operating fluid in the bellows I65 and the reservoir I66 a predetermined amount, the bellows begins to expand downwardly, as viewed in Fig. 3, and, as the bellows continues to expand, the stop member I10 seats on the upper end of the adjusting rod I14. The adjusting rod I14 prevents further downward expansion of the bellows I65 so that subsequent expansion thereof musttake place in an upward direction, as viewed in Fig. 3. Such subsequent expansion of the bellows I65 produces upward movement of the secondary reservoir I66 and the mixing valve I35 to reduce the rate of flow of hot water into the primary mixing chamber 46 and to permit flow of cold water thereinto to begin. The expansion of the bellows I65 continues until a condition of temperature equilibrium has been attained, whereupon the thermostatic means 50 regulates the position of the mixing valve I35 in such a manner as to maintain the temperature of the initial mixture entering the primary mixing chamber 46 substantially constant as will be apparent to those skilled in the art.

It will be noted that the temperature at which the initial mixture is maintained may be varied by varying the position of the adjusting rod I14 to vary the amount which the bellows I65 must expand before the stop member I10 engages the upper end of the adjusting rod. As will readily be apparent from Fig. 3 of the drawings, the position of the adjusting rod may be varied by loosening the nut I 16 and threading the rod into or out of the bore I in the insert member I31. The adjusting rod I14 may then be locked in the desired position by tightening the nut I16. I

As previously discussed, the thermostatic means 50 is preferably set semi-permanently to maintain the temperature of the initial mixture in the primary mixing chamber 46 substantially constant at a predetermined, maximum value. which maximum is preferably equal to the temperature of the hottest water that the averageperson can withstand reasonably comfortably. As best shown in Fig. 3, the thermostat adjusting means Si is normally inaccessible so that the maximum temperature setting of the thermostatic means 50 cannot be tampered with by per-' sons normally using the regulator I5. It will be noted that the adjusting means 5I is rendered normally inaccessible by locating it behind the panel 3i whichcovers the front of the regulator I5. However, if it is necessary to adjust the temperature setting of the thermostatic means 50 for any reason, the panel 3I may be removed to permit access to the adjusting means 5| by service personnel.

It will be noted that since the thermostatic means 50 includes both the bellows I65 and the secondary reservoir I66, a much larger volume of the temperature responsive operating fluid may be employed than would otherwise be possible. v Consequently, any fluctuations in the maximum temperature of the initial mixture which result from fluctuations in the temperatures in the hot and cold water, or from other causes, produce relatively large changes in the total volume of the operating fluid. Since the volume of the secondary reservoir I66 is fixed, such changes in the volume of the operating fluid must be compensated for by expansion or contraction of the bellows I 65, depending upon whether the volume changes result from temperature increases or temperature decreases.

Consequently, if the volume of the bellows I65 is small as compared to that of the secondary reservoir I 66, which is preferably the case, a given change of the volume of the operating fluid produces a relatively large change in the length of the bellows. Thus, the construction illustrated is, in effect, an amplifying system which converts a relatively small change in the temperature of the initial mixture into a relatively large'change in the length of the bellows I65 so that the response to even small fluctuations in the temperature of the initial mixture is quite sensitive. Consequently, if the temperature of the initial mixture should deviate from the predetermined maximum value for any reason, the bellows I65 produces a relatively great movement of the mixing valve I to compensate for such a deviation almostinstantaneously.

Since the thermostatic means is preferably adapted to maintain the temperature of the initiai mixture substantially constant at a specifled maximum value, such as 115 F., for example, the

thermostatic means need operate through only a small range of temperatures extending from say 5 F., for example, below the specified maximum value to a temperature of say 2 F., for example, above the specified maximum. Preferably, all of the expansion and contraction'of the bellows I takes place within this range. Consequently, the volume of the bellows I65 may be made very small as compared to the total volume of operating fluid. In order to permit the use of such a, small bellows I65, the bellows and the secondary reservoir I66 are preferably filled initially by compressing or collapsing the bellows to its minimum length, as determined by engagement of the stop member I10 with the head member I68, and by subsequently filling the bellows and the secondary reservoir with operating fluid at a temperatrrc corresponding to the lower limit of the desired range of action. When the system is fi led with operating fluid in this manner. it will be apparent that the bellows I66 will not begin fluidreaches the temperature .atiwhlch the sys-:

tern was-filled, which temperature may, for example, -bebelow the specifiedmaximum temperature of the initial mixture as: previously mentioned. Thus,- thebellows I85, will expand from its minimumlength to its maximum length for achange in the temperature'oithe operating fluid of say -7- for example, small deviations in the temperature of the initial mixture from the specified maximum value will produce relatively large displacements of the mixing valve I35 tocompensate for such deviations. Consequently, by filling the bellows I65 and the secondary reservoir I55 in the manner described, anextremely accurate and sensitive response to fluctuations in the temperature of the initial mixture results.

Although various fluids which expand and contract with changes in temperature, such as ether, acetone, etc., may be used in the bellows I55 and secondary reservoir "56, I prefer to employ isopropyl alcohol because of its relatively high coemcient of expansion and because of its relatively high boiling point, the latter property being particularly important since it insures that the operating fluid will .remain in its'liquid state at the temperatures at which the thermostatic means 50 is required to operate.

Referring now to Figs. 4 and 8 of the drawings, after the initial mixtur at the maximum temperature has flowed from the primary mixing valve means 49 past the thermostatic means 50,

I so that even lator l5 it leaves the primary mixing chamber through 54 and enters the secthe intermediate passage 55. Simultane ondary mixing chamber or zone ously, cold water may enter the secondary mixing chamber 55 through theauxiliary inlet passage 56' to mingle with the initial mixture entering this mixing chamber, thereby producing a final mixture of a temperature intermediate the temperature of the cold water and the specified maximum temperature of the initial mixture. The relativerates of flow of the initial mixture through the intermediate passage 54 and 0f the cold water-throughthe auxiliary inlet passage 55 are controlled manually by the secondary mixing valve means 51 to obtain the desired final mixture temperature. will be discussed in more detail hereinafter; the secondary mixing valve means 51is adapted to vary the rates of flow of the initial mixture and of the cold water from zero to: a maximum so that final mixture temperature may of the cold. water tothe desired maximum tem: perature-of the initial mixture.

4 It will be apparent that since the temperature-of the "coldwater will normally be'constant be variedfrom the temperature for all practical purposes and since the-tempera I also be substantially conof fiow'of theinitial mixture and of the cold water into the secondary mixingchamber 55 manually. changesin the temperature of the final mix-- ture do not affect the thermostatic means 50 in any way; "Thus, the onlyfunction required of the thermostatic -.means=150' is to maintain the temperature of the initial mixture at the maximuml-value-by comp nsating forchanges in the temperature'ofthe hot water entering the regue would be the case if the thermostatic means were.

required to readjust itself each. time; a diflerent temperature is selected by the'person usingthe regulator.

Moreoven'since thetemperatures of the initial mixture and of the cold water entering the secondary mixing chamber 55are substantially constant, it will be apparent thata substantial portion of the mass of the structure of the regulator l5 will operate at substantially constant temperatures regardless of changes in the final mixture setting. tion of'the massof the regulator l5 operatesTunder conditions of temperature equilibrium, the temperature of the final mixture will respond. to changes in the final mixture temperatures setting very rapidly because of the fact that it, is not necessary to change the temperature of the entire mass of the structure of the regulator each time the temperature setting is changed, which is another important feature of the invention.

Considering the manner in which the temperature of the final mixture is controlled in more detaiLvthe manually operable mixing valve means 51 includes a selector valve 2) which is reciprocable in a bore 2| l in the bodyof the reguas best shown in Figs. 4 and 9.- The intermediate passage 54 for the initial .mixture leaving the primary nates in an annular portion 2l2 which encircles the bore 2| I, and the auxiliary inletpassage56 for the cold water entering the secondary mixing chamber 55 terminates in a similar annular portion 213, the annular portions H2 and 213 being separated by a wall 2 through which the bore 2 extends to receive the selector valve 2H1. The selector valve 2I0 is generally cup-shaped and is provided with a plurality of openings 2l5 in the base wall thereof through which the cold water may flow to mingle with the initial mixture'as will be discussed in more detail hereinafter, only one of these openings being shown in Fig. 9. The selector valve 210 is movable through positions such that any desired relative ratesof flow of the initial mixture and of thecold water into the secondary mixing chamber 55 may be obtained to produce any desired final mixture temperature ranging from the temperature of the cold water-t0 the temperature of the initial mixture. in Fig. 4, at one end of its travel the selector valve 2") is adapted to engage a cylindricalseat2'l8to prevent flow of the initial mixturefrom the annular portion'ZL 2 of the intermediate passage 54 intothe secondary mixing chamber 55. At 'the'other'end of its travel, the rim 2 I 9 of the cupshaped selector valve 210 is adapted to. seat against an insert member prevent flow of cold water from tion 2 of the auxiliary inlet passage 56' into the secondary mixing chamber 55. However, when the selectorfvalve is in anintermediate' position, both the initial mixture and the cold water may flow into the secondary mixing chamber.

Such movement of the selector valve 2 I 0 in the bore 2 is-obtained' by rotation of astem-member222-having a head 223 which is threaded in a counterbore 224 in theinsert member 220, the member 222 being provided with a stem 225 which extends through a counterbore 226 and 9.-

Consequently, since a large pormixing chamber 46 .termi-.

-As best shown 220 in the h re; u to the annular p0rnectlon between the head 223 on the stem memher 222 and the insert member 223 is preferably such that the selector valve 2|. willbe moved through its full range of travel in less than one revolution of the stem member'as will,be discussed in more detail hereinafter.

The stem member 222 is sealed with respect to the insert 220 .by a sealing ring 230 disposed in a groove in the stem 225., and is further sealed with respect thereto by packing 232, the packing being urged into fluid-tight engagement with the stem member and the insert member by a spring 233 which is retained by a snap ring 234, or the like. It will be noted that the packing 232 keeps any water from coming in contact with the threaded connection between the insert member and the head 223 on the stem member 222 so as to prevent corrosion of such threaded connection. The insert. member 220, which is preferably threaded into the bore 2" in the body of the regulator I5, is sealed with respect to the body of the regulator by an annular sealing element 235 disposed in a complementary recess in the body of the regulator, the insert member preferably being provided with an annular flange 238 thereon which seats against the body of the regulator and retains the sealing element 235 in its recess.

The stem member 222 is provided with a flattened projection 239 thereon which is slidably received in a complementary slot 240 in a hub member 2, the hub member having a tapered exterior surface' and being press fitted into a complementary tapered bore 242 in a bushing 243. This bushing extends through a bore 244 in the panel 3| which covers the regulator l5, and is provided with an annular flange 245 thereon which extends into a counterbore 246 in the panel 3|, the flange 245 being disposed between the flange 238 on the insert member 220 and a shoulder 24! formed at the junction of the bore 244 and the counterbore 246 in the panel 3|. The distance between the flange 233 and the shoulder 241 is preferably such as to permit substantially no movement of the bushing 243 axially of the stem member 222 so that any axial movement of the stem member relative to the bushing during adjustment of the selector valve 2|. merely results in sliding movement of the flattened projection 239 on the stem member in'the complementary slot 240 therefor in the hub member 2. The temperature control knob 23 fits over the bushing 243 and is secured to the hub member 2 by a screw 248, or the like, relative rotation between the knob 25 and the bushing being prevented by a key 249.

As previously discussed, whenever the person taking a shower desires to change the temperature'of the final mixture delivered to the shower head 22. it is merely necessary to rotate the temperature control knob 26 in the proper direction as indicated by the words "hot" and cold" adjacent the arrows 35 and 36 on the front panel 3|. Such rotation of the temperature control knob is transmitted to the stem member 222 through the slidable driving connection provided by theflattened projection 239 in the slot 240 so that no movement of the control knob axially of the selector valve bore 2 is required, any tendency for such movement to occur being prevented by engagement of the flange 245 on the bushing 243 with either the shoulder 241, or the flange 233 on the insert member 220. The rotary movement the temperature controfknob 26, the person takcommunicated to the stem 222 in this manner is converted into axial movement of the stem member so as to move the selector valve 2m from ,one to another of its operating positions, thus varying the relative rates of flow of the initial mixture and of cold water into the secondary mixing chamber to vary the temperature of the flnal mixture in the manner previously described. Since the nature of the threaded connection between the head 223 on the stem member 222 and the insert member 220 is such that less than one revolution of the stem member moves the selector valve 2| il throughout its entire range of operating positions as previously mentioned, it will be ap- 1 parent that there will be no overlapping of the graduations on the annular flange 28 of the temperature control knob 28. Moreover, such a threaded connection between the stem member 4 222 and the insert member 220 requires only a relatively small rotational displacement of the control knob 25 fora given change in the temperature of the final mixture so that such a change may be made rapidly by the person taking a shower.

It will thus be apparent that by manipulating ing a shower may obtain a flnal mixture which may range in temperature from that ofthe initial mixture down to the temperature of the cold water, depending upon the position of the selector valve 2||i relative to the cylindrical seat 2 and the insert member 220. If the selector valve 2 I0 engages the cylindrical seat 2|8, the temperature of the final mixture will be equal to that of thecold water since none of the initial mixture can enter the secondary mixing chamber 55,

whereas if the selector valve is in a position such that the rim 2|! thereof is seated on the insert member 220, the temperature of the flnal mixture will be equal to that at which the initial mixture is maintained by the thermostatic means 50 since no'coid water can enter the secondary mixing chamber 55. Any intermediate positions of the selector valve 2| 0 produce final mixture temperatures intermediate the temperature of the cold water and the temperature of the initial mixture.

Asbest shown in Figs. 4 and 9, the final mixture at the selected temperature flows from the secondary mixing chamber 55 past the flow inter- Y rupting means 60 and into the outlet passage 3| by way of "a port 253 which connects the bore 2 for the selector valve m with the outlet passage 6|. As previously discussed, the flow interrupting means is adapted to terminate all flow through the regulator l5 in the event of any mal-functioning or failure of any component of the regulator which would result in a final mixture temperature in excess of a predetermined value, which value is preferably 2 or 3 F., for example, above the temperature at which the initial mixture is maintained by the thermostatic means 50. Thus, the flow interrupting means 63 serves as a safety device which eliminates any possibility of scalding the person taking a shower in the event of any failure of the thermostatic means 50, or any other component of the regulator. which would tend to result in the delivery of water of an excessively high temperature to the shower head 22.:

As best shown in Fig. 9, the flow interrupting means 60 includes a safety valve member 254 having a sealing element 255 thereon which is adapted to seat against a shoulder 256 formed at the junction of the selector valve bore 2| I and the outlet passage CI to interrupt all flow through valve 2l5 and against a snap ring 251 which is disposed in an annular groove 252 in the peripheral wall of a bore 255 in the safety valve member. However, the safety valve member 254 is normally retained in an open position by fusible means 255 as will be described more in detail hereinafter, the fusible means being adapted to soften or melt at a desired temperature to release the safety valve member so that the spring 255 can urge it into its closed position to interrupt flow through the regulator 15, as will be described more'fully hereinafter.

When the safety valve member 254 is in its open position, as shown in Fig. 9 of the drawings, the final mixture may fiow from the secondary mixing chamber 55 into the outlet passage through openings 255 in the safety valve member and through axially extending grooves 251 in the wall of the selector valve bore 2| I. As best shown in Fig. 7, the openings 255 in the safety valve member 254 extend laterally from the bore 255 therein and communicate with the grooves 251.

The fusible means 255 includes a fuse rod 258 which is slidably disposed in a bore 258 in the previously described stem member 222, the rod being provided with a tip 215 having a thin coating of metalthereon which is adapted to melt at the predetermined temperature at which operation of the flow interrupting means 55 is desired. The fusible-coating on the tip 215 of the rod 258 is preferably only a few thousandths of an inch thick so-that' it will melt almost instantaneously if the finalmixture temperature should exceed the predetermined value.

The safety valve member 254 is normally retained in its open position by the fusible coating on the tip 215 of the fuse rod 255, the safety valve member being provided with a retainer 213 which is disposed in the annular groove 252 and upon mel ing of the fusible coating so that the safety valve member 254 may move into its closed position freely in the event that the temperature of the final mixture exceeds the temperature at which the fusible coating will melt.

As previously mentioned, the rod 258 is slidable in the bore 255 therefor in the stem member 222. As best shown in Fig. 9, the rod 258 is resiliently retained in the position required to hold the which is'provided with a plurality of resilient fingers or retaining elements 214 that grip the fusible coating on'the tip of the rod, as best shown in Figs. 4 and 7. The inner ends of the resilient fingers 214 are radiused and are spaced aparta sufficient distance so that they may move freely relative to the tip 215 of the rod 258 in the event that the fusible coating is melted so that the safety valve member 254 may move freely toward its closed position under the influence of the spring 255. However, the fingers 214 of the retainer 213 are sufliciently long to grip the fusible coating'on the ti 215 in a. positive manner to retain the safety valve 254 in its open position under normal conditions, the lengths of the fingers preferably being such that some deflection thereof is normally required in grippin the fusible coating, as shown in Fig. 9. The resilient fingers 214 also preferably grip the fusible coating on the tip 215 of the rod 258 with sufficient intensity to prevent rotation of the rod with the stemmember 222 so as to prevent wear of the fusible coating during normal operation. By making the spacing between the inner ends of the fingers 214 sufilciently small, the fingers will be deflected as shown in Fig. 9 to insure a firm grip on the fusible coating. However, as previously discussed, the spacing between the ends of the resilient fingers 214 must not be so small as to cause binding when the fingers straighten safety valve 254 in its open position by a spring 215, this spring being disposed in a counterbore 216 in the stem member 222 and being seated against a head211 on the rod.

In the event that the temperature of the final mixture should reach a value sufficiently high to melt the fusible coating on the tip 215 of the rod 258, the resilient fingers 214 will disengage the tip of the rod so that the spring 255 urges thesafety valve member 254 toward its closed position. It will be noted that when the safety valve member 254 is seated in its closed position, the pressure of'the water in the selector valve bore 2 will retain the safety valve member in its closed position'in a positivemanner so that no further flow through the regulator can occur. Consequently, it is necessary to re-set the flow interrupting means before the regulator 15 may be used again, it being, of course, necessary to repair the regulator in the event that the excessive final mixture temperature resulted from malfunctioning or failure of some component of the regulator, such as the thermostatic means 55, for example.

In re-setting the flow interrupting means 55, it is necessary to remove the fuse rod 258 and to replace it with a new rod, or to replace the fusible coating on the tip 215 of the oldrod. The .fuse rod 255 may be removed readily by removing the temperature control knob 25 and by removing a screw 215 which is threaded into the counterbore 215 in the stem member 222, this screw being provided with an annular groove for a sealing ring 215 to prevent leakage. The new fuse rod 255 may then be installed and the screw 218 and the control knob 25 replaced. In installing the new fuse rod 255 the spring 215 is depressed sufficiently to permit the coated tip 215 to enter the space between the inner ends of the resilient fingers 214, which then grip the fustible coating on the tip in the manner previously described.

The force applied to the fuse rod 255 by the spring 215 is preferably insufficient to overcome the pressure force exerted on the closed safety valve member 254 by the water, so that it is necessary to shut off the hot and cold water at the source before the new fuse rod is installed and the spring 215 will then restore the safety valve member to its open position. Thus, after any necessary repairs of the regulator 15 have been made and the new fuse rod 258 has been installed in the manner described, the regulator is again ready for operation.

As the final mixture at the temperature selected by the secondary mixing valve means 51 leaves the secondary mixing chamber 55, it enters the outlet passage 5| leading to the flow control means 52, the flow control means being adapted to maintain the rate of flow of the final mixture to the shower head 22 substantially constant at any value selected by the operator as will be discussed in more detail hereinafter. The flow control means 52 is more fully described in my aforesaid co-pending application Serial No. 757,677 and, per se, forms no part of the present invention.

As best shown in Fig. 4, the final mixture may in which encircles the bore 28l adjacent the' port 282 and which communicates with a similar annular passage 288 through a connecting passage 285 which is shown schematically in Fig. 8. However, this connecting passage is located above the broken line 4-4' of Fig. 1 on which the sectional view of Fig. 4 is taken so that it is not shown in Fig. 4. The-body of the regulator I5 is also provided with another annular passage 288 therein which encircles the bore 22! and which communicates with the outlet passage 88 leading to the by-pass and service outlets 88 and 85, the annular passages 284 and 288 being separated by a wall 28.! through which the bore 28l extends to provide a cylindrical seat 288 for a component of the fiow control means 82 as will be discussed in more detail hereinafter.

The .fiow control means 82 includes a valve member 29l which is slidable in' the bore 28| and which is mounted on a rod 292, the valve member being secured to the rod by a screw 298 or the like. The screw 293 also retains a sealing washer 298 which is adapted to seat against a shoulder 295 formed at the junction of the bore 28! and the :port 282 to prevent fiow through the regulator l5. Leakage past the valve member 291 is prevented by a sealing ring 298 which is disposed in an annular groove in the valve member.

Slidably disposed in the bore 28l and encircling the rod 292 is a piston-like valve element 399 which is movable in response to pressure variations in the outlet passage 88 in such a manner as to maintain the rate of flow of the final mixture into the outlet passage 83 substantially constant at a predetermined value as will be discussed in more detail hereinafter. The valve element 388 is provided with'an annular groove 3' therein which communicates with the annular passage 288, and is provided with a. cylindrical portion 302 which is adaptedto engage the cylindrical seat 288 to prevent flow of the final mixture from the annular passage 28 to the annular passage 288 leading to the outlet passage 63. The cylindrical portion 852 is provided with a spiral groove 383 therein which provides fluid communication between the annular passage 288 and a space 384 between the cylindrical portion of the valve element 388 and an insert member 385 sothat the pressure of the final mixture in the annular passage 285- is applied to the end ofthe valve element 388. A spring 388 encircles the rod 292 between the valve member 254 and the valve element 388 and biases the valve element 388 toward a position such that the cylindrical portion 382 thereof disengages the cylindrical seat '288 to permit the final mixture to flow from the an nular passage 284 to the annular passage 288 and thence to the outlet passage 83.

It will be apparent that if therod 292 is moved downwardly, as viewed in Fig. 4, to unseat the, sealing washer 294 on the valve member 29!, the resulting movement of the valve member 29|-is communicated to the -valve element 388 through the spring 388 so that the cylindrical portion 882 of the valve element 888 disengages the cylindrical seat 288. Consequently, the final The regulator l5 888 which is provided by spiralgroove 888' in into the outlet passage 88 through the port 282, the annular passage 288, the connecting passage 285, the annular passage 288, and the annular passage 288. The pressure of the final mixture in the annular passage 288 is applied to the valve. element 888 in such a manner as to move thevalve element upwardly, as viewed in Fig. 4,v byfvirtue or the fluid connection between the annular passage 288 and thespace the cylindrical-portion 882 of the valve element 888. However, such upward movement of the valve element 888, as viewed in Fig. 4, is opposed by the spring 888 which tends to keep the cylindrical portion v382 of the valve element from engagingthe cylindrical seat 288, whereby the valve element'388 seeks a position such that the forces applied thereto by the final mixture in the outlet passage 83 and by the spring 388 are equal. Consequently, if any pressure fiuctuations in the outlet passage 8| occur, such pressure fluctuations result in movement/of the cylindrical Iportion 382 oi the valve element 888 toward or away from the cylindrical seat 288, depending upon whether the pressure fluctuations representpressure increases or decreases, so as to vary the resistance to flow from the annular passage284 to the annular passage 288 in such a manner as to maintain the pressure in the outlet passage 88, and consequently the rate of flow of the final mixture through the outlet passage 83, substantially constant at predetermined values.

It will be apparent that the rate of fiow of the final mixture through the outlet passage 88 maintained by the valve element '388 depends upon the extent to which the spring 388 is compressed between the valve element and the valve member 2!". Thus, by moving the valve member 29! upwardly, as viewed in Fig. 4, to decrease the extent of compression of the spring 888, the rate of flow of the final mixture will be decreased a corresponding amount, and, conversely, by moving the valve member 29! down wardly, as viewed in Fig. 4, to increase the extent of compression of the spring, the rate of flow of the final mixture will be increased since the ,pressure of the final mixture in the outlet passage 83 must increase to balance the increased spring force. Thus, when the valve member 29| is in a closed position such that the sealing washer 298 is seated against the shoulder 295, it prevents any flow through the regulator l5, and when the valve member 29i is moved toward an open position, it unseats the valve element 388 through the action or the spring 388 so that the spring controls the position of the valve element in such a manner as to maintain the rate of flow of the final mixture substantialiy constant at a value which depends upon the position of the valve member 29l.

The valve member 29! is movable through its range of operating positions by axial movement or the rod 292 in the bore 28!, the insert memher 385 being provided with a bore 389 therein through which the rod extends. The rod 292 also extends through vcounterbores 3| 8 and 3 engagement with the rod and the insert'member by a spring-3H seated'against a snap ring 3;

"The rod 292is operatively connected to the flow control knob' 25- in much the same manner as the stem member 222 is operatively connected.-

to the temperature control knob 26 so that a complete description of the connection'between the rod 292 and the knob 26 is not necessary.

,It will be noted that the flowcontrol knob 2! drives a bushing 3! 9 into whicha' hub member M9 is press fitted,the knob being secured to the hub member by a screw 32!! and being keyed to the bushing. The hub member 3!.9 is pro-' detail hereinafter,

-' control means 98 will now Referring particularly to Figs- 3 and 8, the outvided with a slot 32! which slidably receives a flattened projection 322 on the rod 292 so that the'flow control knob 25 may be rotated to produce axial movement of the rod without any axial movement of the control knob itself, any tendency oi'the flow control knob to move axially being prevented by a flange 323 on the bushing 3" which is disposed between a flange the insert member 365 and ashoulder 325 formed onthepanelSi. 7

It will be noted that the piston-like valve eleat its upper end,- as viewed in ment 3!!!! must slide freely in the bore 23! to re- 4 spond rapidly to small pressure fluctuations, thus necessitating a slight clearance between the valve element 306 and the peripheral wall of the bore. Any leakage past the valve element into the space between it and the valve member 29! is permitted to escape through a passage 326 which leads to theby-pass outlet 64, the passage 326 beingshown schematically in Fig. 8.

It will thus be apparent that by the simple expedient of rotating the ilow control knob 25,

. the person taking a shower may obtain any desired rate of flow oi the final mixture at the selected temperature to the shower head 22, limited, of course, to the maximum flow rate possible with the pressures available at the hot and cold water sources. As previously mentioned. the directions of rotation of the flow control knob 25. which are required to increase or decrease the flow rate are indicated by the arrows 33and 34,

respectively, on the panel 3 I. rotation of the knob.

to the end 01' its travel in the direction of the arrow 34 resulting in seating 0f the washer 294 on thevalve. member 29! against the shoulder 295 to. terminate flow through the regulator I5.

The lead of the threads in the threaded connection between the rod .292 and the insert member 305 is preferably such that approximately one and one-quarter revolutions of the flow control knob 25 result in movement of the valve memher I 29! from its closed position to its fully opened position and vice versa. although the lead or such ..threads.may,be varied as desired to re quire any number'of revolutions ofthe flow control knob for a given movement of the valve member. ll also prefer to provide a threaded connection such that approximately one-qua rroi;

a revolution of. the flow control knob 25 is re- 6 quired to move the valve 29! a sufllcient distance from its closed p sitionto unseat the valve element 3!!!! sothat the. remainder of the rotational travel of the flow control knob. may be utilized to control the flow rate of the flnal mixture although. as mentioned above. any desired threaded connection may be employed.

As previously mentioned, the final mixture flowing through the outlet passage-.63 at the selected rate enters either the bY-P S$ Outlet 34 or the service outlet 35, the outlet control means 69 normallyoperatingto deliver the final mixture to the by-pass outlet untilthe temperature of the initial mixture is equal letvalve means g9, which forms partof the outlet control mea s 63. includes a control valve 336 which is axially slidable in a bore 33! in the body of the regulator !5. The bore 33!. is closed Fig. 3, by a head 3.32 \which is retained by a snap ring 333 disposed in a groove in the body of the regulator !6, a fluid-tight seal between the head and the body of the regulator being provided by a sealing ring 334 located in a groove in the head. The bore 33! extends through awall 335 located between the outlet passage 63 and the service outlet to provide communication therebetween and to provide a cylindrical seat 336 for a component of the control valve 330 as will be discussed in more detail hereinafter. The body of the regulator l5 includes a partition 331 which separates the outlet passage 63 and the by-pass outlet 64, this partition having a circular opening 338 therethrough which is of smaller diameter than the 'bore 33! and which provides fluid communica- As best shown in Fig. 3, the control valve 33!! includes a piston 34'! which is slidable longitudinally 0f the bore 33!, and includes a valve head 34! which is connected to the piston by a rod 342. the valve head being provided with a cylindrical surface 343 which is adapted to engage the cylindrical seat 336 to prevent flow of the final mixture from the outlet passage 63 to the service outlet 65 in one position of the control valve 336, end being provided with a tapered surface J 344 which is adapted to engare the partition 33! to prevent flow of the final mixture from the outlet'passage 63 to t e by-pass .outlet passage 34 through the circular opening 338 in another oneratine: position of the/control valve. A spring 345 encircles a stem 346 exten ing from the valve head 34 and is seated a ainst the valve he d.

this spring beine adapted to urge-the control.

valve330 upwardly, asviewed in Fig. 3. toward the position wherein the cylindricelsuriace 353 on the valve head engages the cylindrical seat 336 to prevent flow from the outlet lpassage 63 to the service tlet -65, The stem 346 extending from'the alve head 34! is slidable in a bore 34'! inv the body of thevregulator l5 and serves as a guide for the control valve 336. I

It will be apparent that the spring 33-5 nor! mallv retains ".thecontrol vave 339- in such va position that the valve head 3"! preij'ents-fiow from the outlet pa-sa're 63 to the service outlet, 65, whereby the final mixture flowing through the outlet passage 6.3 is delivered to the by-pass outlet 64. However, whenever the space between the piston 340 and the head 332 contains water under pressure, the pressure force applied to the piston overcomes the force applied by the spring 345 and moves the control valve .336 downwardly, asviewed in Fig. 3, so that the valve head 34! 27 engages the partition 331 to prevent flow from the outlet passage 63 to the by-pass outlet 34, whereby the final mixture flowing through the outlet'passage 63 enters the service outlet 65 and flows to the shower head 22. As will be discussed in more detail hereinafter, water under 7 surface 343 on the valve head 3 engages the cylindrical seat 336 when no water under pressure is being delivered to the space between the head 332 and the piston 343, .a slight clearance is provided between the piston and the wall of the bore 33I to permit leakage pastthe piston into the service outlet 65 so that the fluid pressure in this space may be dissipated.

Referring particularly to Figs. 3 and 10 of the drawings, the pilot valve means 13 is disposed in a bore 35I in the body of the regulator I5 which communicates with the passage 353 leading to the space between the head 332 and the piston 343 on the control valve 333, the body of the regulator also being provided with a passage 352 therein which connects the annular passage 284 adjacent the flow control means 62 to the bore 35I as shown schematically in Fig. 8.

An insert member 353 is threaded into the bore 35I and is provided with an annular groove 354 therein which communicates with the passage 353, the insert member being sealed with respect to the body of the regulator I5 by a sealing ring 355 which is disposed in an annular groove in the insert member so as to prevent fluid leakage between the passage 353 and the passage 352. Leakage past the insert member 353 to the exterior of the regulator I5 is prevented by a gasket 356 which is retained by a cap 351 threaded on the insert member.

The insert member 353 is provided with a bore 363 therein which communicates with the annular groove 354 in the insert member through.

a plurality of openings 36I. The insert member 353 is also provided with a circular opening 362 therein which cooperates with the bore 363 to provide a shoulder 363, and which communicates with the passage 352 through a space 364 between the insert member and the inner end of the bore 35I. A cup-shaped member 365 is disposed in the bore 363 in the insert member 353 and is retained therein by a snap ring 366, a pilot valve:

member 361 being slidable axially in the cupshaped member. The pilot valve member 361 includes a tapered head 363 thereon which is adapted to seat on the shoulder 363 at the junction of the bore 363 and the circular opening 362, and which, when unseated, permits flow from the passage 352 to the passage 353 by way of the space 364, the circular opening 362, the bore 363, the openings 36I, and the annular groove 354. The pilot valve member 361 is normally held in its closed position with the head 363 seated on the shoulder 363 by a spring 31I which is disposed in a bore 312 in the pilot valve member and which is seated against the inner end of the cup-shaped member 365. l The pilot valve member 361 is also provided with a bleed passage 313 therein which permits water from the passage 352 to enter the bore 312 and the interior of the cup-shaped member 365 so as to balance the pilot valve member hydraulically. The pilot valve member 331 is also provided with a stem 315 thereon whichextends through the opening 332 and the space 364 into the bore I36 and which terminates adjacent the cylindrical projection I35 on the head member I63 ofthe thermostatic means 53.

The operation of the pilot valve means 13, and the manner in which it controls the operation of the outlet valve means 63, will now be considered in more detail, it being assumed, for convenience, that the regulator I5 has not been in operation for some time so that the temperature of the initial mixture in the primary mixing chamber 46 willhave fallen well below the" predetermined, maximum value. Under such conditions, the bellows I65 of the thermostatic means 53 will be contracted sufiiciently so that the cylindrical projection I35 on the head member I63 to which the bellows is attached will be disengaged from the stem 315 of the pilot'valve member 361.

However, if the regulator I5 is again placed in operation by rotating the flow control knob 25in the direction of the arrow 33 to actuate the flow control means 62, hot water from the source of supply will enter the regulator through the inlet line I3 to displace any water in the regulatorwhichhas cooled ofl in the interval during which the regulator was inoperative. Consequently, the temperature of the initial mixture in the primary mixing chamber 46 will rise and, as it approaches the predetermined-maximum value, the bellows I65 will expand to operate the primary mixing valve means 43 in the manner previously described so as to maintain the temperature of the initial mixture at the maximum value. Such expansion of the bellows I65 causes the projection I35 on the head member I68 to engage the stem 315 on the pilot valve member 361, thus unseating the pilot valve member so that water may flow from the passage 352 into the passage 353 leading to the outlet valve means 63. Consequently, the resulting pressure applied to the piston 343 of the control valve 333 causes the valve head 3 to assume a position such that the final mixture flows from the outlet passage 63 into the service outlet 65 instead of the by-pass outlet 64 as previously described.

It will thus be apparent that whenever the temperature of the initiaL mixture in the primary mixing chamber 46 falls appreciably below the maximum value for which the thermostatic means 53 is set, the pilot valve means 13 prevents the delivery or water under pressure to the outlet valve means 63 to operate same so that the final mixtureis delivered to the by-pass outlet 64. However, as long as the temperature of the initial mixture is up to, or substantially up to the maximum value, the thermostatic.

means 53 actuates the pilot valve means 13 so that water under pressure is delivered to the outlet valve means 63, thereby routing the final mixture to the service outlet 65 instead of to the by-pass outlet 64'. Thus, the regulator I5 delivers the flnal mixture to the by-pa'ss outlet 64 until normal operating temperatures are attained and subsequently delivers it to the service outlet 65, thereby insuring that no water will be delivered to the shower head 22 unless it is at the temperature selected by the person taking a shower.

' in the service line vent immediate movement of 9 v V Upon completion or a shower, the operato may terminate flow of the flnal mixture to the shower head 22 by rotating the flow control knob 25 to the limit of its travel in the direction of the arrow 34 in the manner previously described. The initial mixture in the primary mixing chamber 48 will then begin to cool to cause the bello s I85 oi the thermostatic means 58 to contrac thus permitting thespring 3' to seat the pilot valve member 381 to prevent further flow of water to the space between the piston 348 of the control valve 338 and the head 332 through the passage 358. passage 352 leading to the pilot valve means 18 is located downstream from the valve member 28! which terminates flow through the regulator IS, the pressure applied to the piston 34!) of the control valve 338 at the instant the pilot valve member 381 seats will be equal to the pressure resulting from the static head of 'water trapped 2| above the regulator l by the valve head 3 on the control valve 338, this static head preferably being suflicient to prethe control valve by the spring 345. However, since a slight clearance is provided between the piston 348 of the control valve 338 and the wall of the bore 33!, any water trapped in the space between the piston 348 and the head 332 and in the passage 358 by seating of the pilot valve member 381 will leak past the piston 348 slowly so that the spring 345 will move the valve head 3 on the control valve 338 slowly from the position wherein it is seated on the partition 331 to the position wherein it engages the cylindrical seat 338. Therate at which water leaks past the piston 348 is preferably sumciently small that all of the water trapped in the service line 22 above the control valve 338-will drain into the by-pass outlet 84 while the valve head 34! on the control valve is in an intermediate position and before it engages the cylindrical seat 338.

It will be apparent that if the water in the service line 2| leading to the shower head 22 were not permitted to drain into the by-pass outlet 84 in this manner, it would be trapped in the service line by the c ntrol valve 338 and would be discharged through the shower head onto the next person taking a shower. If a considerable interval of time elapsed between showers, the water "entrapped in the service line 2| in this manner might be uncomfortably cold. Thus, by avoiding entrapment of water in the service line 2| in the manner described, it is impossible for any water to be delivered to the shower head 22 unless it is at the temperature selected by the person intending to take ashower,

' tated to the limit It will be noted that since the regardless of the position of the pilot valve 2 30 graphs, the actuating means 1| is adapted to bypass the pilot valve means 18 so as to deliver the water required to actuate the outlet valve means 89 directly thereto whenever the temperature control knob 28 is set for a cold shower, 1. e., whenever the temperature control knob is roof its travel in the direction of the arrow 38.

Considering the actuating means 1! in more detail, the body of the regulator I5 is provided with a passage 388 therein which connects the passage 352 leading to the pilot valve means 18 with an annular groove 38l formed in the insert member 228 in the selector valve bore 2! l. The annular groove 38l communicates with another annular groove 382' in the insert member 228 through openings 383, the groove 382 being formed in the wall of the bore 221 in the insert member. The insert member 228 is provided with another annular groove 384 therein which is also formed in the wall of the bore 221, the annular groove 384 being connected to an annular groove 385 in'the exterior of the insert member by openings 388. The annular groove 385 is connected to the passage 358 leading to the outlet valve means 89 by a passage 388 as best shown in Fig. 8. Leakage between theannular grooves 38l and 385 is prevented by a sealing ring 388 which is located in a complementary groove in the insert member 228, and leakage between the annular groove 385 and the auxiliary inlet passage 88 is prevented by a similarly located sealing ring 398. I

It will be noted that when the selector valve 2 l 8 is in an intermediate position, fluid communication between the annular grooves 382 and 384 isprevented by the stem member 222 which is disposed in the bore 221 in the insert member 228. However, the stem member 222 is provided with an annular groove 35" therein which connects the grooves 382 and 384 in the insert member 228 when the selector valve H8 is in a position such that substantially all of the water flowing into the secondary mixing chamber is cold water from the auxiliary in et passage 58. In other words, it the temperature control knob 28 is set for a final mixture temperature whichis substantially equal to that of the cold water so as to obtain a cold shower, the groove 38! in the stem member 222 interconnects the annular grooves 382 and 384 in the insert mem er 228 so that water may flow from the passage 352 to the passage 358 by way of the passages 388 and 388 381. whenever a cold, or substantially cold 18 is by- Thus, shower is desired, the pilot valve means passed so that the water required to operate the this being an important feature of the invention. I

It will be noted that since the pilot valve means 18 does not actuate the outlet valve means 88 to divert water from the by-pass outlet 84 to the service outlet 85 until such time as the temperature of the initial mixture in the primary mixing chamber 48 is substantially up to the specified maximum value, a cold shower cannot be taken until a sufllcient quantity of hot water has flowed through the regulator 15 and out the by-pass line 28 to attain normal operating temperatures. In order to avoid the waste of water and the delay which this wouldentail, I provide the aforementioned means 1| for actuating the outlet valve means 89 independently of the temperature of the initial mixture in the primary mixing chamber 48 when only a cold shower is desired. As will be discussed in more detail in the following paraout et valve means 89 is delivered directly thereto. Consequently, the person desiring a cold shower may, by rotating the temperature control knob toward the end of its travel in the direction of the arrow 38, obtain a flow of water at the desired temperature to the shower head 22 immediate y without having to wait for the regulator l5 to warm up.

From the foregoing description of my temperature and flow regulator l5 it will be apparent that the device maybe employed to deliver water to the shower head 22 at various selected flow rates and at various temperatures, the flow rates attainable ranging from 'zero up to a maximum value which is commensurate with the pressures available at the hot and cold water sources, and 

